SiC semiconductor devices have recently become the focus of attention, which are mainly used for systems in various power electronics fields such as motor control systems and power conversion systems.
Patent Document 1, for example, discloses a vertical IGBT including a p-type SiC substrate (collector layer), an n-type drift layer formed on the SiC substrate, a p-type base region formed in an upper portion of the drift layer, and an n-type emitter region formed in an upper portion of the base region.
Patent Document 2 discloses a trench-gate type MOSFET including an n+-type SiC substrate, an n−-type base layer formed on the SiC substrate, a p-type body region formed in a surficial portion of the base layer, an n+-type source region formed in a surficial portion of the body region, a gate trench penetrating from the surface of the base layer through the source region and the body region, and a gate electrode embedded in the gate trench with a gate insulating film therebetween.